1. Field of the Invention
The present invention is broadly concerned with hydrolyzed jojoba protein and uses thereof, particularly in connection with cosmetic products such as shampoos, shampoo conditioners, hair styling gels, hair conditioners, hair reparatives, bath and shower gels, skin lotions and creams, shaving creams, and sunscreens. More particularly, it is concerned with hydrolyzed jojoba protein which is preferably in the form of a mixture of amino acids, peptides and/or protein fractions derived from the hydrolysis of naturally occurring jojoba protein; such mixtures, when used in cosmetic products provide enhanced properties.
2. Description of the Prior Art
Jojoba is a dioecious wind-pollinated shrub, reaching a height of 1-5 meters and having a long life span (100-200 years). Jojoba is cultivated mainly in Arizona, Northern Mexico, Argentina and Israel. Genetic variability in morphology, anatomy and physiology within the species is very large and enable selection of clones for high yield and other agricultural attributes. Leaves are xerophytic with a thick cuticle, sunken stomata. They contain special tissue with a high concentration of phenol compounds. Flowers are apetalous: the female ones are usually solitary, one per two nodes although flowers every node or in clusters are not rare. The male flowers are clustered. Flower buds form in the axiles of leaves solely on the new vegetative growth occurring during the warm seasons under favorable temperatures and water regime. New flower buds are dormant and will open only after a cool season with enough cold units for the fulfillment of their chilling requirements. Anthesis occurs in the spring when the soil and air temperature rise to above 15xc2x0 C. Severe water stress prevents opening of flowers. The jojoba fruit is a capsule containing one to three dark brown seeds that normally range in their dry weight between 0.5-1.1 g and contains 44-56% wax. Fruits ripen during the spring and early summer and seeds fall to the ground in late summer.
Indigenous Amerinds in the Sonora and Baja, California used jojoba seed and oil for cooking, hair care, and for treatments of many medical problems such as poison ivy, sores, wounds, colds, cancer and kidney malfunction. The oil is extracted from jojoba seed by conventional screw pressing techniques, leaving a residual defatted dry material which is high in native jojoba protein (typically on the order of 25-35% by weight protein).
Jojoba oil is a light yellow liquid at room temperature and is made up of straight-chain esters of mono-unsaturated long chain fatty acids and fatty alcohols and has an average total carbon chain length of 42 carbons. The product may be isomerized, hydrogenated, sulfurized, chlorinated or transesterified, and has a wide range of industrial uses, mainly in cosmetics in which it is incorporated in formulations for skin care preparations such as lotions, moisturizers, massage oils, creams, hair care products, lipsticks, makeups and nail products. Other potential uses include pharmaceuticals and as extenders for plastics, printers inks, gear-oil additives and lubricants.
The present invention is directed to a new form of jojoba protein, namely hydrolyzed jojoba protein and derivatives thereof, as well as uses of such protein products in cosmetic formulations. The preferred hydrolyzed jojoba protein and derivatives thereof in accordance with the invention comprise a mixture of amino acids, peptides and/or protein fractions derived from the hydrolysis of the naturally occurring jojoba protein. Such hydrolysis is preferably carried out enzymatically, but if desired acid hydrolysis can also be employed.
In more detail, the hydrolyzed jojoba protein is typically in the form of a mixture having an amino acid, peptide and/or protein fragment molecular weight range of from about 75-5,000, with an average molecular weight of from about 1,500-2,500. During processing, it is often desirable to membrane filter the hydrolysis products in order to segregate the peptides and/or protein fragments to achieve different molecular weight profiles. In one such preferred method, a hydrolyzed jojoba protein product of relatively high molecular weight is provided, with a molecular weight range for the respective peptides and/or fragments therein of from about 1,000-5,000 and with an average molecular weight of from about 3,000-4,000. Similarly, a lower molecular weight fraction (sometimes referred to as a jojoba amino acid fraction) is produced wherein the respective amino acids and peptides exhibit a molecular weight range of from about 75-1,000 with an average molecular weight of from about 100-300.
Although the hydrolyzed jojoba protein and derivatives thereof can be produced as a dry powder, this is sometimes difficult and normally the product is in the form of an aqueous dispersion containing jojoba protein or derivatives at a level of from about 18-35% by weight, more preferably from about 23-27% by weight.
As used herein, xe2x80x9cderivativesxe2x80x9d of hydrolyzed jojoba protein refers to changes in the structure of the individual amino acids, peptides and/or protein fragments produced by amino acid addition, deletion, replacement, substitution and/or modifications; mutants produced by recombinant and/or DNA shuffling; quaternized species; and all other chemically synthesized/modified forms of the individual amino acids, peptides and/or protein fragments which retain at least in part some activity of the initial hydrolyzed amino acids, peptides and/or protein fragments. One particularly preferred class of hydrolyzed jojoba protein derivatives is the lipid derivatives, especially those synthesized using C12-C22 fatty acids.
The term xe2x80x9chydrolyzed jojoba proteinxe2x80x9d is intended to embrace and cover not only the amino acids, peptides and/or protein fractions derived from the hydrolysis of naturally occurring jojoba protein but also all xe2x80x9cderivativesxe2x80x9d as herein defined.
The jojoba products of the invention can be used to good effect in a variety of cosmetic formulations which include at least one ingredient selected from the group consisting of humectants, emollients, conditioners, thickeners, moisturizing agents, opacifiers, pearl agents, buffering agents, slip agents, feel agents, anti-static agents, acidifiers, preservatives, film formers, plasticizers, setting agents and suspending agents (usually, each of the foregoing ingredients when used is present at a level of from about 0.05-10% by weight). An amount of hydrolyzed jojoba protein or derivative thereof is incorporated into this type of cosmetic formulation, usually at a level of from about 1-10% by weight, more preferably from about 3-8% by weight. Inasmuch as the preferred jojoba protein products are in the form of liquid dispersions, it is a simple matter to add the jojoba to the cosmetic formulations during preparation thereof. Generally, the formulations of the invention comprise from about 10-95% by weight water, more preferably from about 20-75% by weight water.
Among the cosmetic products which can benefit from incorporation of the jojoba products of the invention are those selected from the group consisting of shampoos, shampoo conditioners, hair styling gels, hair conditioners, hair reparatives, hair tonics, hair fixatives, hair mousses, bath and shower gels, liquid soaps, moisturizing sprays, makeup, pressed powder formulations, lip products, bath additives, sanitizing wipes, hand sanitizers, premoistened towelettes, skin lotions and creams, shaving creams, and sunscreens. In products of these types, the shampoos and shampoo conditioners further comprise at least about 6% by weight detergent; the hairstyling gels further comprise a gel-forming polymer system; the hair conditioners further comprise at least about 0.3% by weight cationic hair conditioner; the hair reparatives further comprise at least about 2% by weight cationic hair conditioner; the bath and shower gels further comprise at least about 25% by weight surfactant; the skin lotions and creams further comprise at least about 2% by weight of a cream former and emollients and/or oils; the sunscreen further comprising a sunblocking agent; and the shaving creams further comprising at least about 10% by weight detergent or alternately at least about 3% by weight of a soap and having a basic pH.